I've read the description that in terms of sound it sits between en PAF humbucker and a single coil and I think that is indeed the best description.
Fatter than a single coil and more sparkly that a PAF humbucker.
The value of the capacitor that you use, determines where the peak of the resonance frequency of the over-tones sits, higher value capacitor = lower frequency peak. So to keep the sound sparkly, use a low value capacitor like 22nF. The resistance dampens the peak, as the resitor is shorted to the ground, a high value resistor will result is less damping and a low value resistor in much damping.
Without any capacitor and resistor, the sound is a bit thin and overly bright.
The dimensions of the pickup are huge, so you can't simply swap a normal humbucker for a CuNiFe. A normal covered humbucker is around 70mm wide, these are 78mm wide.